Abstract of the paper: We investigate the influence of community networks on Internet traffic via content delivery (CDN) and peer-to-peer (P2P) overlays. Efficient traffic engineering by network providers and on global delivery platforms mainly depends on mechanisms on the application overlays, which select sources and paths for delivery within distributed systems partly with integration into clouds. Peer-to-peer communities often exchange data between the user’s terminals via unnecessary long transport paths which introduce high load on network links and delays. Content delivery networks provide network storage and caches for shortening the transport paths but are seldom optimized over domains under different administration e.g. between CDN providers and ISPs. We show the visibility of community networks in traffic profiles and study their effects on traffic engineering from the perspective of network providers including current standardization in working groups at the Internet Engineering Task Force.